Rotary punch

ABSTRACT

There is disclosed a rotary punch for punching a series of holes through paper or cardboard or the like, comprising a pair of counter-rotating rolls one of which has punch elements protruding from the periphery to mate with corresponding die holes at the periphery of the other roll. Each of the punch elements, which may be removed and replaced without disassembling the punch, comprises a cylinder with a punch head at one end, held in place by a pair of converging walls against which the cylinder is held by a spring-loaded ball pressing against a recess in the cylinder. The die holes are serrated and are of harder material than the punch, which initially is unserrated and of slightly larger diameter than the internal diameter of the die serrations so that the punch head becomes correspondingly serrated upon a punching operation.

United States Patent 1191 Grano 1 Aug. 13, 1974 [5 ROTARY PUNCH Primary Iiruminer-Andrcw R. .Iuhusz Assistant Examiner-W. D. Bray [75] Inventor' James Gram Temple City Cahf' Attorne Agent, or Firm-Donald D. Mon; D. Gordon [73] Assignee: Tools and Production, Inc., Temple Angus City, Calif. V

[21] Appl 300l00 There is disclosed a rotary punch for punching a series of holes through paper or cardboard or the like, com- [52] US. Cl 83/345, 83/670, 83/698 prising a pair of counter-rotating rolls one of which [51] Int. Cl B23d 25/12 has punch elements protruding from the periphery to [58] Field of Search 83/174, 670, 698, 690, mate with corresponding die holes at the periphery of 83/685, 308, 345, 104, 673 the other roll. Each of the punch elements, which may be removed and replaced without disassembling the [56] References Cited punch, comprises a cylinder with a punch head at one UNITED STATES P NT end, held in place by a pair of converging walls against 2,085,863 7/1937 Lindbom 83/345 x the P h by F ban 2,116,391 5/1938 Gochoel i i 83/345 pressmg against a recess 1n the cylinder. The die holes 2,141,492 12/1938 Southwick. 83/345 X are serrated and are of harder material than the 3,106,859 10/1963 Huffman 83/345 punch, hi h initially is unserrated ,and of slightly 3,541,656 11/1970 Devon 1. 83/698 X larger diameter than the internal diameter of the die 3,563,124 2/197l Gargrave 83/698 serrations so that the punch head becomes correspondingly serrated upon a punching operation.

11 Claims. 10 Drawing Figures PATENTEDMIWIBH 3.828.682

' SHEEI 1 (IF 2 ROTARY PUNCH This invention relates to paper punches and more particularly to punches of the rotary type which punch a series of holes in paper or cardboard or like material.

It has been known to perforate the margins of strips of paper or cardboard, for example tickets, with spaced holes, and rotary punches have been used for the purpose. Such a punch mechanism has comprised a pair of mating rolls, one of which is provided with peripheral punch elements which protrude outwardly from the roll, and the other of which contains peripheral die holes spaced the same distance apart as the punch elements so that the punch elements register with and enter respective die holes and thereby punch out the material between them.

Some difficulty has been experienced in the use of such rotary punches due to the fact that individual punch elements sometimes become worn out, broken or damaged, requiring their replacement. Damage or malfunction has also been experienced due to imperfect alignments or mating of parts. In heretofore known constructions, the replacement of a punch element has required disassembling the punch mechanism to remove and replace such elements.

An object of the present invention is to provide such a rotary type punch in which the mating punch and die elements are accurately aligned and produce an efficient punching operation. A related object is to provide a construction which permits removal and replacement of punch elements without the necessity for disassembling the punch structure.

Another object is to avoid excessive wear, deterioration or damage to the die holes.

The invention is carried out by provision of a pair of rolls which are counter-rotating on parallel axes, one containing spaced die holes, and the other containing correspondingly located punch elements which successively protrude into respective successive die holes. The roll containing the punch elements is made from an assembly of parts including provision of individual spring-loaded members for positioning the individual punch elements against respective aligning surfaces. The arrangement is such that each punch element is held by a three-place contact. A feature of the individual punch elements resides the provision of recessed v portions to be engaged by the positioning elements.

A highly preferred feature resides in making the material in which the die holes are formed harder than the material of which the punch elements are made, so that the punch elements will fail first, following which they can be replaced.

A further preferred feature resides in serrating the walls of the die holes and providing that initially the peripheral punching edges or surfaces of the punch elements are unserrated but of a diameter equal to or approaching the diameter of the die holes at the roots of their serrations. Since the punch elements are of softer material than the die holes, serrations will be formed at the engaging peripheral surfaces of each punch element as soon as a punching operation is performed.

A further feature resides in a construction of the roll containing the punch elements in a plurality of parts which meet together. Ordinarily there will be two mating parts suitably fastened together as by bolts.

I with the roll containing the die holes.

The foregoing and other features of the invention will be better understood from the following detailed description and the accompanying drawings of which:

FIG. 1 is a side view, partly in cross-section of a rotary punch according to this invention showing the position of paper or material having holes punched through it;

FIG. 2 is an end elevation view of the rotary punch of FIG. 1;

FIG. 3 is an exploded view of the punch roll of FIGS. 1 and 2 illustrating its assembly;

FIG. 4 shows a detail, taken at line 4--4 of FIG. 1, of a portion of the punch roll of FIGS. 1 and 2 containing several punch elements;

FIG. 5 shows in cross-section part of the punch roll illustrating the mounting of one of the punches as seen from the side of the punch element;

FIG. 6 shows in cross-section a detail of one of the punch elements mounted in its position in the punch roll;

FIG. 7 shows a detail of one of the punch elements used in the rotary punch of FIGS. 1 and 2;

FIG. 8 shows an enlarged detail of part of the die roll of FIGS. 1 and 2, and a die hole containing a serrated wall;

FIG. 9 shows a cross-section view of the punching portion of the punch of FIGS. 4 and 6 containing serrations formed after a first punching operation; and

FIG. 10 illustrates a portion of a strip of material containing holes punched by the punch of FIGS. 1 and 2.

Referring to FIGS. 1 and 2 there are shown two cylindrical rolls l0 and 11 of equal diameter with a strip of material such as paper or cardboard l2 therebetween. Roll 10 is referred to herein as a punch roll since it supports punch elements 13 protruding outwardly from its periphery. Roll 11 is herein referred to as a die roll since it contains a number of peripheral die holes 14 to receive the heads of punch elements 13 for punching holes through the material 12. The punch roll and die roll are mounted for rotation on respective parallel shafts l5 and 16 which will be geared together by suitable gear elements (not shown) so that the punch roll and die roll will rotate simultaneously at the same peripheral speeds but in opposite directions as indicated by respective arrows 17 and 18.

Referring particularly to the exploded view, FIG. 3, the punch roll comprises three co-axial rings 19, 20 and 21, each made up of two half rings fitted together. The ring 19 has a raised hub 22 having a central cylindrical opening 23 just largeenough to fit over shaft 15 to which it is keyed by a key 24 fitted into a key-way 24a and a corresponding key-way 25 in the shaft. Concentrically around the hub 22 the ring 19 is provided with an outer annular portion 26 having a surface perpendicular to the axis of the shaft. There are formed through this annular surface a substantial number of equally spaced holes or bores 27 all of equal diameter and arranged in a concentric circle, corresponding to the number of punch elements to be used in the rotary punch.

The annular ring 20 is dimensioned to fit over raised hub 22 and on the flat annular surface 26 of ring 19, the outer diameter of rings 19 and 20 being the same. Ring 20 is provided with the same number of holes 28 as the number of holes 27, and similarly spaced around a concentric circle of the same diameter as the circle of holes 27. The diameters of all the holes 28 are the same and less than the diameters of holes 27. The annular ring 21 likewise fits over hub 22 and overlies ring 20. Ring 21 is provided with a number of holes 29 of equal size and spaced equi-distant apart through each of which an assembly bolt 30 extends when the roll is assembled.

Ring 19 is provided with the same number of holes 31 as the number of holes 29, and placed at positions corresponding to the positions of holes 29 so that the bolts 30 can thread into respective holes 31 which are tapped for the purpose. Since these bolts each pass through ring 20, ring 20 is likewise provided with a set of holes 32 dimensioned and positioned so that bolts 30 can protrude through them. I

Considering the particular bolt 30 shown in FIG. 3 this will be passed through the particular hole 29a of ring 21 which is beneath it and likewise through the particular hole 28a of ring 20 and through the particular hole 31a of ring 19. A number of spaced positioning pins 32 protrude from annular surface 26 to pass through similarly positioned holes 33 through ring 20 and similarly positioned holes 34 through ring 21. Considering a particular one of these pins 32a it passes through the particular holes 33a and 34a when the roll is assembled. 7

Punch elements 13 are held in recesses 36 formed around the inside of ring 21. The manner of holding these punch elements is illustrated more particularly in FIGS. 4, 5, 6 and 7.FIG. 4 shows a portion of the outer periphery of roll and its recesses 36 containing punch elements 13. Referring to FIG. 5 which is a cross-section view taken at line 55 of FIG. 4, there is shown one of the holes or bores 27, the particular one shown in FIG. 5 being designated 27a, which may correspond with the same numbered bore 27a in FIG. 3. Within this bore there is placed a compression spring 37 (it being understood that the illustration in FIG. 5 is upside down relative to the illustration in FIG. 3) and over the free end of the helical spring there is placed a ball 38 which protrudes into and part way through the particular hole 28a of holes 28 which is in the corresponding position. The ball 38 will not pass all the way through hole 28a because the ball is of somewhat greater diameter than that of the hole. The ball does, however, protrude far enough through ring so that it engages the corresponding punch element 13 in a manner described as follows: the side of ring 21 adjacent the ring 20 contains the recesses 36 within which the respective punch element is fitted. Referring particularly to FIGS. 5 and 6, the recess 36 is provided with a pair of sides 39 and 40 which converge from parallel sides 41 and 42 toward each other in the direction away from the ball.

Each punch element 13 is constructed with a solid cylinder 43 having a circumferentially grooved portion 44 intermediate the ends of the cylinder. The groove is formed by two frusto-conical surfaces 45 and 46 converging toward each other toward the central axis of cylinder 43 and meeting a relatively short cylindrical section 47 of lesser diameter than that of cylinder 43. The punch element is provided with a punching head 48 having a flat surface 49 perpendicular to the longitudinal axis of the punching element receding in a conical surface 50 to meet the forward end of cylinder 43.

In the machining of the punching element there will ordinarily remain in small protuberance 51 centrally located at the rear face 52 of the punch element. To provide for this, the edge 53 of hub 22 (FIG. 5) is provided with a slot 54 large enough to accommodate protuberance 51 so that the two abutting faces 52 and 53 can lie flat against each other.

It will be convenient before attaching the punch elements to the punch roll, to first assemble the punch roll. This can be done by joining the two sections 19a and 19b ofring l9 and firmly securing them by bolts 55. To be assured ofa very precise joinder of parts 19a and 19b, the abutting face of one of the parts 19a is provided with a semi-cylindrical recess 56 extending across both sides of its abutting face 57, and the corresponding abutting face of the other part 19b is provided with a corresponding mating semi-cylindrical bulge 59 which mates practically perfectly with recess 56. After placing all of springs 37 in their respective bores 27 and loading the respective balls 38 on the springs the two halves of ring 20 are positioned together and brought against the balls with the ballsprotruding part way through respective holes 28 and with positioning pins 32 through their respective holes 33 and through respective holes 34 of ring member 21 whose two parts are now abutted together. In this condition, the bolts 30 are threaded into their respective tapped holes 31 to tighten down the assembly.

The punch elements 13 can then be attached in their respective recesses 36. To facilitate passage of the rear sectionof cylindrical portion 43 of the punch element past the ball, the rear part of the rear section is provided with a chamfer 72 of about 45 to the longitudinal axis. By pushing or tapping the front surface 49, the chamfer will serve to push on the ball and compress the spring sufficient to allow passage of cylindrical portion 43 so that surfaces 52 and 53 abut each other. In this position the ball is pressurized by thespring against cylindrical section 47 which presses cylinder 43 against recess walls 39 and 40, where the cylinder 43 is in line contact with these walls 39 and 40 and the ball is in point contact with cylindrical surface 47 of the punch element. There is allowed some clearance between the ball surface and at least one of surfaces 45 and 46, and likewise there is clearance between the ball surface and at least part of hole 28, so that the ball is free to move slightly relative to that hole and relative to surfaces 45 and 46 when pressed against cylindrical surface 47. Thus, the punch element is aligned in its proper protruding position by its two lines of contact with recess surfaces 39 and 40.

The die holes 14 are formed or bored very accurately to have their centers spaced exactly as the center of the punch elements. Around the side surface of the die there are provided holes 60 which meet the respective die holes 14, so that punchings of material 12 can pass out of the mechanism through holes 60.

The material of the die roll, at least in the region of the die holes, is made harder than the material of the punch head, and furthermore the interior surface of each die hole is provided with serrations 61 (FIG. 8) extending parallel to the axis of the die hole. Initially the punching surface 49 of the punch head is in the form of a circle without any serrations, and the diameter of that circle is almost equal to the diameter of the circle 62 of the roots 63 of the serrations and greater than the diameter of circle 71 of the peaks of the serrations. After a punching operation in which the punch head 48 is forced into the die hole, the peripheral edge of the punch head, being softer than the material of the die, becomes serrated by the serrations of the die hole, the serrations 64 of the punch head being indicated in FIG. 9. Thus the roots 63 of the die hole serrations are of equal diameter to that of the peaks 65 of the punch head serrations, and the roots 66 of the punch head serrations are equal in diameter to the peaks 67 of the die hole serrations. The effect of the serrations is to provide a perfect fit of each punch element with its respective die hole, thereby producing an efficient punching out of the material and resulting in prolonged life of the parts. i

It will be recognized that the correlation between the punch elements and the die holes must be very exact so that when a punch element meets its mating die hole, the punch head fits snugly and exactly in the die hole. To insure this result, adjustments are provided. Thus when the punch roll and die roll 11 are mounted on their respective shafts l5 and 16, and keyed to their respective shafts by respective keys 24 and 68 and the shafts coupled together by the proper gearing, proper positioning of the punch roll relative to the die roll may be had by set screws or bolts 69 and 70. Punch roll 10 may be set in the proper position longitudinally of its shaft 15 by tightening screw 69 against shaft 15 at the proper position of the shaft, and any undesired play between key 24 and its key slots can be taken up by tightening set screw 70 against the key. Proper rotational angularity between the two rolls may be adjusted by suitable set screws in their coupling gearing (not shown).

The operation of the rotary punch is apparent from the foregoing description. The coupled shafts 15 and 16 will be rotated by a suitable motor and a sheet 12 of material which is to have holes punched in it will be fed between the rolls. During this feeding, successive punch elements will punch through the materialinto respective successive die holes of the die roll, providing a line of punched holes 71 in the material 12 (FIG. 10). If the material 12 be a relatively narrow strip of material which it is desired to perforate at both sides as shown in FIG. 10, such as for example a strip of tickets, it may be desired to attach an additional set of the punch and die rolls on the shafts 15 and 16. If the material 12 be a sheet of material which is to have only a single row of perforations, such as along the margin of a sheet of paper, the single pair of rolls shown in FIGS. 1 and 2 will be sufficient.

When on occasion, a punch element becomes broken or damaged, it may be pulled out of its recess by grasping the punch head 48 with a suitable tool, and the camming action of conical surface 46 of the punch element will cam on ball 38 to force the ball against the compression of the spring so that the punch element can be extracted. A new punch element can then be inserted as described above.

It will be recognized that by this invention there is provided a very efficient and accurate punch capable of long and trouble-free life, and easy to service when punch elements need replacement.

Modifications may of course be made by those skilled in the art without departing from the scope of the invention.

It will be understood that the embodiments of the invention illustrated and described herein are given by way of illustration and not of limitation, and that modifications or equivalents or alternatives within the scope of the invention may suggest themselves to those skilled in the art.

I claim:

1. In a rotary punch of the type having a pair of rolls counter-rotating on parallel shafts with the peripheries of the rolls closely adjacent, one of said rolls being a punch roll containing a plurality of spaced punch elements protruding from its periphery and the other roll being a die roll containing a plurality of similar spaced die holes at its periphery so that while counter-rotating, successive ones of the punch elements engage successive ones of the die holes whereby material inserted between the rotating rolls is caused to travel between the rolls and become perforated by a series of holes punched through it by the successive punch elements, the improvement comprising:

a. a recess in the punch roll for each punch element, each recess having a pair of opposed supporting surfaces which converge toward each other in the direction of the deepest part of the recess;

b. each punch element having a central axis and comprising a head at one end and having a cylindrical peripheral sidewall containing a circumferentially grooved portion having a pair of walls which converge toward each other in the direction of the central axis of the cylindrical periphery and having an inner wall joining the converging walls;

0. a locking ball at said grooved portion; and

d. resilient means urging said ball into contact with said inner wall of the grooved portion in a direction to cause the cylindrical periphery to maintain engagement with both said opposed supporting surfaces of the recess.

2. Apparatus according to claim 1 in which the punch roll contains a bore for each punch element and the spring means is a compression spring in the bore.

3. Apparatus according to claim 1 in which the punch roll comprises three rings overlying each other and fastened together, a first of the outer rings containing a plurality of said recesses around its periphery facing the other rings, the second outer ring having a plurality of bores having openings facing the first ring, said resilient means being a spiral spring under compression in each bore and spring loading a respective one of the balls located at the end of the respective spring facing the first ring, the third of the rings being sandwiched between the first and second rings and having a plurality of holes through which parts of the respective balls protrude to engage the punch element, whereby the punch elements may be extracted from the punch roll and may also be inserted into the punch roll and locked by the ball.

4. Apparatus according to claim 3 in which each of the three rings is formed in a plurality of parts joined together.

5. Apparatus according to claim 3 in which each of the rings is formed in two parts joined together.

6. Apparatus according to claim 1 in which the material of the die roll at the die holes is harder than the material of the punch head.

7. Apparatus according to claim 6 in which the die holes have serrations on their walls parallel to their axes.

8. Apparatus according to claim 7 in which the outer diameter of the punch head is larger than the inner diameter of the die hole.

9. Apparatus according to claim 7 in which the punch head has serrations corresponding with the serrations of the corresponding die hole so that when the punch conical.

"22%; UNITED STATES PATENT OFFICE I CERTIFICATE OF CORRECTION Patent No. 3,828,632 Dated August Inventor(s) JAMES V. GRANOv It is eertified that error appears in the above-idehtified patent and that send Letters Patent are hereby corrected as shown below Col. 3, line 43, (Claim 2, line 3) Signed and js ea ledith is 19th day of November 1974.

(SEAL) Attest:

McCOY M. GIBSON JR, C. MARSHALL DANN Attesting Officer Commissioner of Patents 'spring" should read --resilient-- 

1. In a rotary punch of the type having a pair of rolls counterrotating on parallel shafts with the peripheries of the rolls closely adjacent, one of said rolls being a punch roll containing a plurality of spaced punch elements protruding from its periphery and the other roll being a die roll containing a plurality of similar spaced die holes at its periphery so that while counter-rotating, successive ones of the punch elements engage successive ones of the die holes whereby material inserted between the rotating rolls is caused to travel between the rolls and become perforated by a series of holes punched through it by the successive punch elements, the improvement comprising: a. a recess in the punch roll for each punch element, each recess having a pair of opposed supporting surfaces which converge toward each other in the direction of the deepest part of the recess; b. each punch element having a central axis and comprising a head at one end and having a cylindrical periphEral sidewall containing a circumferentially grooved portion having a pair of walls which converge toward each other in the direction of the central axis of the cylindrical periphery and having an inner wall joining the converging walls; c. a locking ball at said grooved portion; and d. resilient means urging said ball into contact with said inner wall of the grooved portion in a direction to cause the cylindrical periphery to maintain engagement with both said opposed supporting surfaces of the recess.
 2. Apparatus according to claim 1 in which the punch roll contains a bore for each punch element and the spring means is a compression spring in the bore.
 3. Apparatus according to claim 1 in which the punch roll comprises three rings overlying each other and fastened together, a first of the outer rings containing a plurality of said recesses around its periphery facing the other rings, the second outer ring having a plurality of bores having openings facing the first ring, said resilient means being a spiral spring under compression in each bore and spring loading a respective one of the balls located at the end of the respective spring facing the first ring, the third of the rings being sandwiched between the first and second rings and having a plurality of holes through which parts of the respective balls protrude to engage the punch element, whereby the punch elements may be extracted from the punch roll and may also be inserted into the punch roll and locked by the ball.
 4. Apparatus according to claim 3 in which each of the three rings is formed in a plurality of parts joined together.
 5. Apparatus according to claim 3 in which each of the rings is formed in two parts joined together.
 6. Apparatus according to claim 1 in which the material of the die roll at the die holes is harder than the material of the punch head.
 7. Apparatus according to claim 6 in which the die holes have serrations on their walls parallel to their axes.
 8. Apparatus according to claim 7 in which the outer diameter of the punch head is larger than the inner diameter of the die hole.
 9. Apparatus according to claim 7 in which the punch head has serrations corresponding with the serrations of the corresponding die hole so that when the punch head becomes inserted in the die hole, the serrations of the punch head and die hole engage each other.
 10. A rotary punch according to claim 1 in which there is clearance between the ball and at least one of said converging walls of the grooved portion.
 11. A rotary punch according to claim 1 in which the converging walls of the grooved portion are frusto-conical. 